Bridges

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Revision as of 21:29, 26 March 2014 by Fredrik (talk | contribs) (Example)
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Introduction

A bridge works like a transparent switch/hub between two or more interfaces and clients on any of the bridged interfaces can communicate with each other exactly as if they were part of the same network. For bridging two interfaces in two geographically separate locations over a tunnel see the article on EtherIP.

Example

Below is a complete configuration in plain-text for bridging two local interfaces with each other and clients behind both interfaces sharing the same DHCP Server, default gateway and firewall rules. This can of course be configured using the graphical web administration, as well. Pay particular attention to the fact that the vr2 interface does not have any IP address assigned to it and the clients will instead use the IP assigned to vr0 as their default gateway.

firewall {
	pass quick on lan label LAN
	pass in log quick on mgmt proto tcp to (mgmt) port {$mgmt_ports} label management
	match out on wan inet nat-to (wan:0) label NAT
	pass out quick on wan label outbound
}
interface bridge0 {
	firewall {
		skip
	}
	member vr1
	member vr2
}
interface vr0 {
	description "Internet"
	group "wan"
	dhcp-client
}
interface vr1 {
	description "LAN"
	group "lan"
	group "mgmt"
	address 192.168.1.1/24
	dhcp-server {
	}
}
interface vr2 {
	group "lan"
	group "mgmt"
}
system {
	authentication {
		user "admin" {
			password "admin"
		}
	}
	dns {
		name-server 8.8.8.8
	}
	http-server
	ssh-server
}